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>Appendix G. Command-Line Options</TD
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><H1
CLASS="SECT1"
><A
NAME="STANDARD-OPTIONS"
></A
>G.1. Standard Command-Line Options</H1
><P
>Over time, there has evolved a loose standard for the
        meanings of command-line option flags. The GNU utilities conform
        more closely to this <SPAN
CLASS="QUOTE"
>"standard"</SPAN
> than older UNIX
        utilities.</P
><P
>Traditionally, UNIX command-line options consist of a dash,
        followed by one or more lowercase letters. The GNU utilities
        added a double-dash, followed by a complete word or compound
        word.</P
><P
>The two most widely-accepted options are:</P
><P
></P
><UL
><LI
><P
><TT
CLASS="OPTION"
>-h</TT
></P
><P
><TT
CLASS="OPTION"
>--help</TT
></P
><P
><I
CLASS="FIRSTTERM"
>Help</I
>: Give usage message and exit.</P
></LI
><LI
><P
><TT
CLASS="OPTION"
>-v</TT
></P
><P
><TT
CLASS="OPTION"
>--version</TT
></P
><P
><I
CLASS="FIRSTTERM"
>Version</I
>: Show program version and exit.</P
></LI
></UL
><P
>Other common options are:</P
><P
></P
><UL
><LI
><P
><TT
CLASS="OPTION"
>-a</TT
></P
><P
><TT
CLASS="OPTION"
>--all</TT
></P
><P
><I
CLASS="FIRSTTERM"
>All</I
>: show <EM
>all</EM
>
        information or operate on <EM
>all</EM
> arguments.</P
></LI
><LI
><P
><TT
CLASS="OPTION"
>-l</TT
></P
><P
><TT
CLASS="OPTION"
>--list</TT
></P
><P
><I
CLASS="FIRSTTERM"
>List</I
>: list files or arguments without
        taking other action.</P
></LI
><LI
><P
><TT
CLASS="OPTION"
>-o</TT
></P
><P
><I
CLASS="FIRSTTERM"
>Output</I
> filename</P
></LI
><LI
><P
><TT
CLASS="OPTION"
>-q</TT
></P
><P
><TT
CLASS="OPTION"
>--quiet</TT
></P
><P
><I
CLASS="FIRSTTERM"
>Quiet</I
>: suppress
      <TT
CLASS="FILENAME"
>stdout</TT
>.</P
></LI
><LI
><P
><TT
CLASS="OPTION"
>-r</TT
></P
><P
><TT
CLASS="OPTION"
>-R</TT
></P
><P
><TT
CLASS="OPTION"
>--recursive</TT
></P
><P
><I
CLASS="FIRSTTERM"
>Recursive</I
>: Operate recursively (down
        directory tree).</P
></LI
><LI
><P
><TT
CLASS="OPTION"
>-v</TT
></P
><P
><TT
CLASS="OPTION"
>--verbose</TT
></P
><P
><I
CLASS="FIRSTTERM"
>Verbose</I
>: output additional information to
        <TT
CLASS="FILENAME"
>stdout</TT
> or <TT
CLASS="FILENAME"
>stderr</TT
>.</P
></LI
><LI
><P
><TT
CLASS="OPTION"
>-z</TT
></P
><P
><TT
CLASS="OPTION"
>--compress</TT
></P
><P
><I
CLASS="FIRSTTERM"
>Compress</I
>: apply compression (usually
        <A
HREF="filearchiv.html#GZIPREF"
>gzip</A
>).</P
></LI
></UL
><P
>However:</P
><P
></P
><UL
><LI
><P
>In <B
CLASS="COMMAND"
>tar</B
> and <B
CLASS="COMMAND"
>gawk</B
>:</P
><P
><TT
CLASS="OPTION"
>-f</TT
></P
><P
><TT
CLASS="OPTION"
>--file</TT
></P
><P
><I
CLASS="FIRSTTERM"
>File</I
>: filename follows.</P
></LI
><LI
><P
>In <B
CLASS="COMMAND"
>cp</B
>, <B
CLASS="COMMAND"
>mv</B
>,
        <B
CLASS="COMMAND"
>rm</B
>:</P
><P
><TT
CLASS="OPTION"
>-f</TT
></P
><P
><TT
CLASS="OPTION"
>--force</TT
></P
><P
><I
CLASS="FIRSTTERM"
>Force</I
>: force overwrite of target file(s).</P
></LI
></UL
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><P
></P
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><TD
ALIGN="LEFT"
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><P
>Many UNIX and Linux utilities deviate from this
      <SPAN
CLASS="QUOTE"
>"standard,"</SPAN
> so it is dangerous to
      <EM
>assume</EM
> that a given option will behave in a
      standard way. Always check the man page for the command in question
      when in doubt.</P
></TD
></TR
></TABLE
></DIV
><P
>A complete table of recommended options for the GNU utilities
        is available at <A
HREF="http://www.gnu.org/prep/standards/"
TARGET="_top"
>the GNU standards page</A
>.</P
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